Pelias

Pelias (died 1300 BC) was King of Iolcus in the Greek mythology. In 1300 BC, Medea convinced his daughters to kill him after Pelias refused to grant Jason his throne in exchange for the Golden Fleece.

Biography
Pelias was said to have been the son of the Greek god Poseidon, who disguised himself as a river god to have sex with King Cretheus of Iolcus' wife Tyro. Tyro left Pelias and his twin brother on a mountain, hoping that they would die, but a herdsman raised them as his own children, and Pelias, when a grown man, would kill Tyro's stepmother Sidero in a temple to Hera for having mistreated Tyro. The power-hungry Pelias went on to become King of Iolcus, and he sought domination over all Thessaly. He banished his half-brother Aeson to the dungeons, where he married and had his son, Jason. Jason was raised by Chiron, and Pelias soon saw Jason as a threat. Pelias decided to send Jason on the seemingly-impossible task of retrieving the Golden Fleece from Colchis, promising him the kingship if he succeeded. Although Jason succeeded in this task, Pelias received news that the Argo had sunk, and he told this to Aeson and to Jason's brother Promachus, both of whom poisoned themselves out of despair. When Jason returned to Thessaly with his wife Medea, Pelias refused to give up the throne to Jason, so Medea plotted to murder him. She convinced Pelias' daughters that killing and dismembering an old goat would restore it to its younger health, and she demonstrated the ritual successfully. After seeing a young goat leap from the cauldron where the old goat had been killed, the excited daughters killed and dismembered Pelias, only to find that they had murdered him.